Gear-cutting machine.



w. P. ZIMMERMANN.

GEAR CUTTING MACHINE. APPLICATION FILED 00124, 19o?.

Patented Aug. 13, 1912.

10 SHEETSSHEBT l.

@7m away@ W. F. ZIMMERMANN. GEAR CUTTING MAGHINF.v` APPLICATION FILED 001224, 1907.

Patented Aug. 13, 1912.

10 SHEETS--SHEET 2.

W. F. ZIMMERMANN. GEAR CUTTING MACHINE.

APPLICATION FILED 00T. 24, 1907. 1 ,085,5 1 1 Patented Aug. 13,1912.

10 SHBETSH-SHEET 3,

W. F. ZIMMERMAINN. GEAR CUTTING MACHINE.

APPv IVl'IOZ' FILED 00124, 1907,

Patented Aug. 13, 1912.

W. F. ZIMMERMANN.

GEAR CUTTING MACHINE.

APPLIOATION FILED 001224, 1907.

113535,51 1, Patented Aug. 13,1912.

l0 SHEETS-SE T n u a wim/5885s:

l/WENTR W. F.y ZIMMERMANN.

GEAR. CUTTING MACHINE.

APPLIOATION FILED 00T. 24, 1907.

Patented Aug. 13, 1912.

l0 SEEETSWSHBBT 6.

WIYNESSES:

W. F. ZIMMERMANN. GEAR CUTTING MACHINE Patented Aug. 13, 1912.

AYPLIOATION FILED 00T. 24, 1907.

v m g )Wim/5555: 24M m w. P. ZIMMBRMANN.

GEAR CUTTING MACHINE.

APPLICATION FILED 00T. 24, 1907. 1,035,51 1 Patented Aug. 13,1912.

10 SHEETS-SHEET 8.

l 70 if a Patented Aug. 13, 1912.

10 SHEETS-SHEET 9.

W. F. ZIMMERMANN. GEAR CUTTING MACHINE.

APPLIOATION FILED 00124, 1907.

W. F ZIMBRMANN.

GEAR UUTTIN'MAoHINE. APPGHIN FILED 00T. 24, 1907.

1,035,51 1. Patented Aug. 13,1912.

nali-"-A UM A n unirse' srntrss PATENT oFFioE.

WILLIAM r. ZIMMERMANN, or NEWARK, NEW Janse?, Assieme. To GoULn et Eisma@A4 HAR-DT, OF NEWARK, NEW' JERSEY, CORPORATIGN 0F NEW JERSEY.

GERFCUTTING MACHINE.

Specification of Letters Patent.

Patented Ang. 13, 1912.1

Application led October 24, 1907. Seriell Ho. 399,033.

To all ywhom it may concern Be it known that l, immun F. Zuumn MANN, a citizen of the United States, re-

siding at ben'ark, in the county of Esser:

and State oi New Jersey, huye invented certain new and useful improvements in Genn Cutting Machines, of .rhieh e following is :i specification.

The invention relates to machines to generate the teeth upon gear blanks, more espe.- cially to machines for generating the teeth of spur, spiral und chevron or herringbone gears with u helical or hob cutter.

lt has heretofore been thecustom to generate the teeth ot spiral und chevron gears with a hob or helical cutter, by a structure which produces a. resultant. mot ion in either the gen1' blank or the helical cutter from two independent component mutionsgone of the seid component motions controlled bythe a l- Vance or iced o'l" the cutter, and the other by the rotations or' the said cutter; the tive component motions substnntiullyl combined into the said resultant motion by what is known in the nrt as dicrential gearing. Further, the teeth of spiral gears here been generated with a helical cutter, by a mechanical structure based on a mathematical formula, thus eliminating the necessity of any differential (rearing. For this structure an application for a. patent has been filed February 18th. 1907, the serial number of' which is 357,782. However, in the seid npplicntion the advance of the helical cutter is controlled by the rotations of the seid cutter, which has the disadvantage of the feed changing, for the clierent numbers of teeth, when keeping the feed change gears the saine. Thot is, it has been found by experiment, that a given materia-l will allow a certain amount of feed for every revolution of the `sible cases that muy arise.

seid blank, which contains a given number of teeth, und il this number of teeth was in creased to twice the original number in the next blank to be cui, the feed would be double the originel amount per revolution ot the said gear blank, if no change was made in the eeti, gearing'. flhis consequently necessitates the changing ot the t'ecd for the different numbers of teeth for the same niaterial, which requires :t wide ronge or feeds to obtain the maximum output in all the pos 0i' it ymay bc slated that in the ibove structure tor every increase of number o'teeth, the iced gears ployed, which were,

remaining the same, the feed er revolution of the blank is altered. The eed per revolution being the measure of the length of feed marks on the face of the gear, deter-y mine the quality as well as the rapidity of i Another feature of the ,invention relates to provisions whereby the structure readily, lends itself to cut the converging angles of". chevrcmVA ears simultaneously With one Stting of t e machine', `enabling-the blank to be mede in one to practically less than one half of the time consumed in the methods generally emto cut the two angles separately and bolt ward.

flhe structure is further applicable in that; i i

tiro cutters/,can simultaneously operate upon the teeth of spurand spiral gears at one and the sinne time. One of the seid cutters being o triflein ad. ance of the other, the

forinerfcutter acting as the roughing out and the latter as the finishing cutter.

Further features of the invention relato to a quick return to the cutter, whereby the' .9!)

cutter is rapidly returned to its ori inal sition by power to take a re-cut. he quick return feature is especially7 adapted to the generating of spiral and chevron' gears,l

when taking a recut, inasmuch as the nick 95.

return does not disturb the setting o the machines, aswould be the case when'returning the cutter by thehand feed wheel.y

provided in the machine.

Other features relate to means to readily reverse the'feed, whereby the helical or hob cutter can be fed in the-pro er direction when cutting either right or le t hand gears. The invention still :further relates to a novel arrangement of compound and idler gears constituting the change gears of this struct-ure', whereby the proper numberlpf teeth and proper angle of the gear beingcnt v is obtained.

Anotl'lerfeature relates to the construc- 11()A spiral and chevron 65y piece, and thereby reducing. Z5! the time to pro nce the said chevron gears i them together afterchine, embodying the invention, the adjustythe gears on the lower or index driving removed, and also showing the adjmating the assumption being that the gear Wasi right. hand, using a right. hand cutter.

The various features and Combinations Constitut-ingthe invention, will be readiiy understood from the following detail description of the struct-ure as shown in the accompanying drawings of which Figure l is a front elevation of the maable cutter sta-nehion having been removed to more Clearly show the cutter and its .parte upon the stationary stanohion. Fig. i? is a ight side elevation 'with the driving one removed to clearly illustrate the structure it Would ordinarily cover, and Fig. 3 is ieit side elevation ot the maline, et is a. rear elevation showing the index Fig. 5 is` e. plan section at El X of Fig. 2 showing clearly the cutter drive reversing mechanism, the cutter feed arrangement, the quick return to the cutie and the inoexing mechanism for the bla-ri iindle. Fig. o is a side elevation of the el( return mechanism shown in Fig. 5 and. Fig. .7 is a. section al; a aof Fig. G illustra-ting the oiutch shifting device. Fig. 8 isv e. rear elevation oi the indexing and feed change gears, and Fig. 9 is a. side elevation of the saine with Shaft in section to olenriy show their arrangement. Fig; 10 is an end section at of Fig. 5, iliustreting the feed reversing mechaniem, and Fig. 11 is en end elevation of the same. F ig. 12 is a section at Ig/ y ot' Fig. 1 through the cutter spindle and driving mechanism therefor, and Fig.' 13 is a lateral section at o C oi `the/Cutter spindle shown in Fig. 12. Fig. is a section at Z Z of Fig. 3 showing the index Wheel, the Work table, and the. Carriage for the same, and the work arbor. Fig. i5 is' a section at d d of Fig. 14 showing'the index worin and the micrometer -adjustrnent for the work spindle, and' Fig. 16 isa eeetion through the said micrometer adjustment at e e ot' Fig. 15. Fig. 17 is an end section through vw w of Fig. 2, showing the feeding mechanism for the eutter,'the main driving shaft and the cutter reversin mechanism, 18, 19 and 20'are detai s ot the reversing gears for the vadjustable stanohion cutter drive, said st-anehion is located on the left end oi Fig. 2. Figs. 21, 22 und 23 illuetrate the feeding mechanism for the cutter on said adjustable stanchion. Fig. 24: is n section at V V of Fig. 2 showing the cutter 'feeding and' the driving mechanism t'o said adjustl able stanehion.v Fig; Q5 is a plan-view ofi Fig. 24 Aaf'itlit-he said adjustableA etanchion mechanism for the stanohion and Work slide.

Referring to Figs. 1, 2, 53, and e upon the base 1, and preferably in one piece with the same is mounted a stanchion 2, also :i Seoond stanchion 2a slidaby mounted on said base 1 and longitiidiuailyadjustable thore-v ou. Euch of said Staiiehioin; Q and "2 ha Ye slidably mounted thereon, the ruth-a' varriage 3 and 2i resperiirely which are vertically adjustable.

Referring more particularly to Fig. 12 which is a section through the Putter Carriages 3 und 3, the Slide t is mounted augularlyv adjustable upon the said Cutter rarriage l and Serin-ed thereto in itsl Various angular positions by the bolts 5i, located iu the circular T Slots (5 and 7; upon said augularly ediuetable Slide 4i mounted a rutter support 8 longitudinally adjustable thereon. fr Icutter spindie is rotatably mounted in said Support 8; the holiral out- -ter 1() is keyed to said spindle 9, and is rotatable therewith, and secured end-wise by the uut 11 and the collar bushing 12. The collar bushing 12, rotates in the outer support 1B, and provided with the buehiug 1li i stoned therein. Upon the other oud of said cutter spindle l) in keyed a driving center 15, which is slidabiy keyed within the spindle gear 11i which meshes with the Spindle driving pinion l?. The spindle il. is provided with a (collar 1S, preferably iu one piece with said spindle 9, between the buahinge 1S) and 2l) which are secured within the `euttei"support 8. The bushing 2O being secured to take the end thrust oi the lepindle 9, due to the angular pressure oi' the helical cutter 10, when operating upon a gear blanli',tlie friction oif 'said end thrust is mate ially reduoedby the miti 'friction washers 21, and 22; a elanip nut 22:5 is provided 'in take up the end wear that may 'haveii'ieulted from the laid end thrust. The

spindle is provided. with a. dust collar 2l, lo atedat the Cutter end to prevent any dust or chips working their way into the spindle bearings. The said spindle gear 1G is held from lateral movement by the easing 25, and the flange 2G secured to said easing the said easing Q5 is bolted to the augularly adjustable slide The cutter lspindle S) and its-suppmt S are w tudinally upon the slide el to Het the heliral cutter 10 centrally. The slide #1 is provided with a tongue 27 engaging a groove in the support-8, and-ac-.tingaf a guide; the said cutter support 8 is adjusted by means ot' a screw 28, which istapped in the slide 4 and operates bot'weenthe abutments 20 and is secured to the slide 8 in carb of its adjusted positions by means of lheT bolts C30, arranged in the T slots 31 provided in the Slide rihe pinion 17 which meshes with the gear 1G extended on each side and is rotaiahly mounted within the bushings which are fastened within the slide i. Upon one oud of said pinion 17 and rotatable therewith is keyed a bevei gear 232i, meshing with a buig hubbed bevel gear 234i rotatably mounted arranged to .slide lungh and secured to the carriage 3.

Cit

within the slide 3. The bevel gear 34 is thecenter about which the singularly adjustable :slide t is rotated. Keyed to the end ot the hub ot said bevel gear 34 and rotatable therewith is another bevel gear' 35 meshing with a sleeve bevel gear 36, slidably keyed upon the vertical drive shaft, 37 and adj ustable therewith; the vertical drive shaft 3T connecting with the main driving mechanism as hereinafter set forth.

The cutter carriage 3 is arranged to slide vertically upon'the ways 38 and 39 of the stanehion 2, and is suitably held thereto by the gib 4t) and the strap vstl. The cutter 10 and its slides' 3 and 4 are counterbalanced by the weight 42, Suspended by the. cable 43 passing over thetsheave wheels 44 and 45, The said sheave wheels dit and 45 are rotatably mounted in the bracket etti which is fastened to the top of the-stanchion 2. The' above descriptitm ofthe cutter 1t) and its slides, ete.. on the stanchion 2, apply also to the cutter. ete. upon the stanchion exact duplicates.

telerring to the Figs. 2, 5 and 1T, the vgrlical cutter drive shaft 3? has keyed to its lower end a bevel gear et?. the upper end bein;r mounted in suitable bearings-in the bracket' 't. the said' bevel gear 47 meshing with the egt-ar 48 keyed to the longitudinal shat't -t9 and rotatable therewith. The said bevel gear 4T is arranged to be alternately engaged by the reversing bevebsleeve pinions .3() and 5l, and driven thereby. The said reversing pinionsot) and 51 are splined to the main driving shaft 52 and are rotatably mounted within the longitudinally adjustable easing 53. lhe said casing 53 slides within the cone bearing 54, andois operated b v means of a lever 55, tulerumed at 5t', in the eone bearing 5l and secured in itsI adjusted positions by the bolt. G0. 'lhe main drive shatt is driven by a cone 57, rotatably mounted upon the bearing 54; the outer t'at'eo't said cone 5T is providedwvielv -liec't'fsses to" 'engage with the projections upon -l-he flange. 59. vrlhe flange 59 is keyed to the main shaft 52 and is rotatable therewith, and transmits motion from the cone 57 to the. main drive shaft 52. Upon the. other end ot' said main shaft. 52 is keyed a Worin til, driving the worin wheel G2 which is rotatably mounted within the quick ret-urn box 63, and also loosely rotates upon the index drive, shaft 6ft; n. bevel gear (35, rotatingin the opposite direction to said worm wheel (32. also loosely rotates upon said index 'shaft (S4 and within said quick return box 63. The. worm wheel (32 and the bevel gear 65 are each provided with a series of clutch teeth upon their faces titi and ($7 respec-tively, which are alternately engaged by a sliding clutoh member (SS, operated by a level' 69, which is fulcrumed in said box 2a, they being.

63 and engages a peripheral groove 70 by means of a clutch shoe 71, eccentrically mounted in said lever 69 and locked in its various positions by a screw 72.- The bevel gear 65 meshes with the' bevel gear 73 secured to one end of the short shaft 74, a spur, gear 7 5 is keyed to the other end, which isz driven by the spur gear 158 keyed to the main shaft 52 and is rotatable therewith.

Upon the end of the index shaft 84 is keyed and rotatable therewith a change gear 76 meshing with a second change gear 77. loosely mounted upon a compound stud: 7S, and keyed to the compound bush 81, the compound stud 78 is carried by a swinging shoe 79, revolving about the index shaft 84 as a center, and is secured in its adjusted positions by the bolts 80; keyed to the cornpound busb 81 is another change gear 82, arranged to engage either direetly with the change gear 83 on the index drive shaft 64 or through the compound change gears '84 and S5, loosely mounted upon the stud 88, and carried by th'e` second compound shoe as a center and is held in its adjusted posigagging `therewith by means of a Worm 93 jourualed in the bearingsprovided in the connection between the gear 91 andvthe worm wheel 92, the latter bemglyed to the index worxn shaft 9414 which isf-'secured ,the inde "worm 95 preferably in one piece tln-rewltln The end wearof the index worm worm shaft. 94 is rotatably mounted in-ra swinging arm 97 pivoted Von the trunnions 9b and 99 secured in the bracket 100 whiclnis suitably attached tothe Work slide 101.y i- 'Elie work slide 101 is adjustably mounted on horizontal guide-ways 102 proyidedeupon the main framel and,seem-ediifnlposition by the clamp plates e, 103 gandft'he clamp, screws .1(l. Atc ireidarnape vided iusaid' vvorkslidefltl o.-. 1ee eive the 'shank of the circular work table 105 "which is rotatably mounted therein andhas-its inner and outer rims .supported by' said slidev lttt to better enablethe-taking ot' heavy Cuts. rlwo antisfrietion washers .106 are placed between the work table 105' and said slide 101 to reduce the friction vwhen cuttingv a SG, swingingaboutthe index drive shaft 64 re' yis pro- 'p tions by the bolts S7. The said change'gear Lsleeve gear. 90 is a gear 91 loosely'mounted, upon the hub of theworni wheel 92 and en* hub of'said gear 91, thus making a positive I 95 is compensated for by a clamp nut 96,' the Loenen gear blank, to a minimum. yPreferably in one piece with saidtable 105 is an index Worm wheel 107 which is split, to more accurately produce the teeth therein the lower Shelf 108 is bolted to the upper halt' by means of bolts 109, the said wheel 107 being driven by the index worm 95. 'lhe work `table 105 is provided with a taper aperture therein, in which a tapered work mandrel 10 coupling 110 is'inserted and secured to the table 105 by bolts 111. The said coupling 110 is also provided with a taper aperture to receive the work mandrel 112 which is inserted and ejected byva differential nut 113. l i

`.the axis of the Work mandrel is arranged to be operated by the index shaft 8-1. Reterring to Figs. 5, and 11 upon the index shaft is secured a spur gear 111 upon the hub of rwhich is rotatably mounted a tuinbler lever 115, carrying the tumbler gears 116 and 117, the tumbler gear 110 meshing yWith the gear 114 and engaging the other tumbler gear 117. The tumbler gears are used to alter the direction of the feed; the tumbler lever-115 is secured in position by the bolt 118. The spur gear 110 is keyed to rthe shaft 120 and arranged to be engaged "by either of said tumbler gears 116 and 117. 3Q The other end of the shaft 120 is arranged to receive the change gear 121 vwhich engages with the change gear 122, keyed to the feed -worni shaft '123. The feed Worin 121 prei .-.erably in one piece with the said worm shaft 123 engages the feed Worin Wheel 125, which is loosely mounted upon the feed screw v.126 which engages a nut port-ion in the Slide 3. The face of said .worm wheel 125 is `irovided with clutch teeth, see Figs. 2 Van 17, which are enga ed by the sliding *dutch-127 which is sli ably keyed to the feed screw 126 and rotates therewith, derivinggits motion from vthe feed Worin Wheel 125.' The feed clutch is engaged by a clutch fork-128 operated manually by the lever 120 'orautomatically by the rod 130 attached thereto, and controlled vby the abutment 131 bolted tothe slide 3 and engaging the docs 132 adjustable upon ,said Arod 130. s stated, the "'cutter and slides upon the ad- 'justable stenchion 2, and the counterbal- ,anee, therefor, are merely duplicates of the parts upon the stationary stanchion 2, to which A.the above description also applies.

Referring to Figs. 18 to 2e, the cutter upon the adjustable stanchion 2a is driven a bevel -gear .1.33 splined to the horizont-al s aft 4:9 engagingr the bevel gear 134 secured tothevertical drive shaft 13.5 which is identical with the vertical drive shaft 37 inthe "stationary stanchion 2. `'l`hefeed to the cutter upon the adjustable stanchion 2 is similarly driven by a screw 136 ta ped in :the slide 3f, and receives its motion yone the eed Worm wheel 137, loosely mounted upon The feeding of` the cutter 10' parallel to the screw 130 and having clutch teeth provided. upon one face to engage with the clutch member 13S slid-ably keyed to the vfeed screw 13G and rotating therewith. The feed worin wheel 123'? is driven by the worin 130 which has keyed to it, the bevel gear 140 which can be engaged by either of the feed reversing gears 11.1 and ,142 slidably keyed upon the feed worin shaft 123. The said feed reversing gears 14-1 and 142 are rotatably inountcd in a sliding bracket 143 operated by the lever letz-ithrough the frame 1, und secured in position by the bolt 115.

The' feed clutch 138 is engaged by the clutch fork 110 which has attached to one end the rod 1117, the said rod 14T is attached to the lever 148 which can be controlled manually or mechanically by the slide 3a, similar to the arrangement upon the stationary stanrhion by the abutment 140 engaging one oi' the dogs 150 upon` the rod 151, which is attached to the handle 148. The above described arrangement for driving und feeding the cutter upon the adjustable stauchion 2,a is all arranged upon the lower end of said stanchion 2 and slides therewith. The longitudinal adjusting of said stanchion 2a is ueci'iniplished by a screw 152 tapped in saidstauchion 2 and operated by a hand wheel 15?, located upon one end of the machine. rThe hand wheel 153 has attached to it a gear 154- which meshes with the slidable keyed gear upon the stanchion adjusting screw 152and also with a similarly mounted gear 150 upon the Work slide adjusting screw 157'u'hich adjusts the work slide 101. The gears 155 and '150 are slidably f mounted so that either the stanchion 2a or 'the Work slide 101 can be adjusted individually or simultaneously when setting for depth or diderent diameters of blank.

The operation ot the machine for cutting spur gears is as toiloivs1-The blank to be cut is secured to the work mandrel 112. The helical cutter 10, is then secured to the cut-- ter spindle 0, by the nut 11. Thev swivel slide 4, upon which the cutter 10 is mounted, is adjusted to an angle equal to the angle of the helices of the cutter, and secured 'to the slide The feed gears 121 and 122, are placed upon the shafts and 123 respectively according to amount ot feed required. The change gears for the indexing are placed according;` to the formula upon the shafts G1 and 81 and the compound studs 78 and 88. @ne of the tumbler gears, 116 or 117, is engaged with the gear 119, upon the feed worin driving' shatt- `120, to feed the cutter in the proper direction. A lso one ofthe cutter reversing gears 50er 51, is engaged with the bevel gear 17, on the vertical cutter drivin shaft 37, by means of the handle 55.' The 6eed clutch 127 is engaged with the feed worm lwheel 125 by means of the hanformula C, the spur gear 90 rotating with the index shaft 84, drives the sleeve gear 91 which is coupled to theindexing worm 95, through the vadjusting worm and Worm Wheel 93 and 92 respectively, the said Worm 95 engaging the index worm Wheel 107, Which rotates the gear blank to be cut.

The cutter is driven from'the main driving shaft 52, vthrough one of the slidingA bevel gears 50 or 51, theproper one having been engaged as heretofore explained. The vertical cutter drive shaft 37, ,fwhich is driven from the sliding bevel gears through the bevel gear 47, drives the long hubbed bevel gear 34, mounted as a center for the swivel slide 4 to revolve about, through the bevel gears 36 and 35. The said long hubbed bevel gear 34 drives the gear 33 which rotates the pinion 17. The said pinion 17, drives the cutter spindle gear 1 6, which rotates t-he cutter 10. y

The feed to the cutter is operated fromy the index shaft 84, through one of the tumbler gears 116 or 117, 'connecting the gears 114 and 119, upon the shafts 84 and 120 respectively. Motion is then transmitted from the shaft 120 through the change gears121` and 122 to the feed Worm shaft 123, which drives the feed Worm Wheel 125, through the Worm 124. The feedscrevv 126 is coupled to the feed vvorm Wheel 125 by the clutch 127 Whenboth stanchions are. employed to cut spur gears, the cutter upon'the adjustable stanchion is driven bythe bevel gear 47, upon the vertical cutter drive shaft 37l in the stationary' stanchion. The said bevel gear 47 engages with the bevel .gear 48,upon the horizontal shaft 49, which rotates the splined bevel gear 133, the said bevel gear 133 driving the verticalcutter drive shaft 135, through the bevel gear 134. The cutter mounted upon the adjustable stanchion is driven from the'vertical drive 135, similar as outlined above for the opposite cutter.

The feed for the cutter upon the stanchion 2f* is driven from the extension of the feed Worm shaft 123, upon-which the sliding bevel gears 141 and 142, are splined. One of said sliding feed gears drives the bevel Agear 140, which rotates the feed'worm 139,5.l

which drivesvthe feed screw136, in a similar manner to the feed screvv 126. The dogs 132 and 150'iare set to throw out the feed clutches 127 and 138, when thecutter has passed across the faceof the' gear being cut. The blank `is 'thendisengaged from the cutter and tiffohk return is enl'` gaged by the clutch 68. The bevel, gear 65,. is then driving the index drive shaft'64 from the main drive shafthrough the gears 158,". and 73. The face offthe clutch 68 which.

engagesthe face 66'ofthc worm wheel 62, Vis so arranged as to only engage in one o sition. This clutch bein so .arranged al ows of the rapid ,'return' .o the 'cutter without disturbing the setting of the indexing If the gear blank requires another cut, the proper depth 1 is adjusted and the feed clutches again engage and the machine again begins to operate.

- i For` cutting s lral gears, the machine is o set similarto w en'spur gears arecut, but

with this vexce tion, the cutter is'not only set at an angle eq "ai tothe llfelices of the cutter, l

,but to a still greater angle which' is equal to the sum of the angles; ofthe helices of the cutter and the spiral blank to be cut. The

index change gears .upon the shafts 64 and 84 are placed according to the formula `co'r,Nc 1 CNPNQIF Vsin.X l Both stanchions can also-be used to out spiral gears, both cutters feeding in a dp'vvni Ward direction. V

Chevron gears are generated kwith both cutters operatin upon the wheel blank siy multane'ously...l pe of the cutters'is set to` cut the right hand helices andis a right P hand cutter; the other, to cut the left hand helices, is'aJ left hand cutter. Furthermore,

one cutteri is fed downward and theother y upward, 1t being ,immaterial Whichf' way eitherl cutt'r `isfedfjt only being necessary to feed in ,pp'osite direction.

The cutter driving arrangement 4is so arf,

, rangedjhat only one setv of reversing gears are necessary, that is, if the cutter is .rotat' 'ing in the proper direction onone` stanchion, 'ii' the other cutter will also .j rotate properly. The fecd necessarily requires t'wo sets ofrefl versmg gears dueto the requirement of feeding the cutters either in the same directionv I or in opposite directions.

Both cutters receive their prliper of rotations from one cone, and their proper'. feed from one set'of change wheels.f""Fur v; ther-more, the indexing is also,y controlled from one source only, and that is, through thechange gears connecting the shaftti 84. (lneor two compounds can 'be When one compound 1s used,f"right 1- kann helical gearscan be Loenen helical critters. Reterring to Figs. S and 9, the compound gear 82, is directly engaged with the gear S3 upon the index drive shaft 6% when one compound is used. l?, however, from the ratios obtained by the ornnila7 it is neeessar \Y to use two compounds when cutting right hand gears. to maintain 'the proper direction of the shaft; Sel, an intermediate is inserted. ll'hen this intermediate is inserted, the change gears connect the shafts 64 and Si as shown in the Figs. S, where the compound gear 82 engages the idler or intermediate gear 89. said idler S9 engaiing the. second compound gear and the compound gear S5 mounted with said compound gear S-l. meshes with the gear 83 on the shat't G-t.

1Vrvhen leit't hand gears are eut by lett hand helical cutters and only one compound. is used, ity is necessary to insert an idler or intermediate to obtain the proper direction of the wheel hlanl. rllhis is aceomnlishedlby engaging the compound gear with the compound gear 85, Said gear 83 meshing With the gear @.3 on the shaft 6. "When it is necessary to use two compounds `for lett hand gears, the proper direction is obtained Without an)Y further gears.

Haring described my intention and its mode oit operation, l claim as new and desire to secure by Letters Patent the t'ollou'ing:-

l. In a gear cutting machine the combination of a main drive shaft, a cutter earriugi'c, a cutter mounted upon said earriage and angular-lY adjustable thereon. reversing gears mounted upon' said main drive sha't't and. rotatable therewith` niiereby 'the direction of rotation of said cutter can be versed, i feed shatt to actuate said cutter carriage, an index shaft. a sniz'nlle carriage with a spindle rotatable therein actuated by Said index shat'tr` a train ot gearing connecting said main drive shaft and cutter. a second train connecting said main drive and index shafts. a third train connecting said index and feed shafts, said trains designed to produce a fixed relative rotational ratio `between said cutter and spindle and produeing a. feeding motion relative to the rotar tion ot' said spindle. l

9.. ln a gear cutting machine the cominnation ot a main drive shafha cutter car-4 ringe7 a cutter mounted upon said carriage and angolari;7 adjustable tlnu'eon. a te l shaft. to act nate said earring an index shaft. a spindle carriage with a spin-:lie rotatably mounted therein, actuated bjr said iudex shaft, a train of gearing connecting said main drive shuit and cutter, a second train ot' gearing connecting said main drivev and index shafts, a third train connecting said index and feed shafts, comprising` reversing gears, whereby the teed can be reversed, sa id trains designed to produce a fixed relative rotational ratio between said cutter and shaft, a spindle rarriage, with a spindle ro- 4 nitably mounted therein actuated by said index shaft, a train o gearing connecting said main drive shaftand cutter, a second train of gearing connecting said main and index shafts., a third train connecting said index and feed shafts, comprising tumbler gears whereby the feed can be reversed, said trains designed to produce a fixed relative rotational ratio between said cutter and spindle and producing a feeding motion relative to the rotations of said spindle, to vproduce substantially a motion in a helical line passing around the axis of said spindle.

l. The combination of an index shaft 84, and index drii'e shaft. G-l, a change gear S3 mounted on said index drive shaft Gl and rotatable therewith and a second change gear 89 loosely mounted thereon, a conipound stud, compound gears Sl and 85 rotatable thereon and meshing with said Years Si! and S25 respectively, a second coniound stud7 compound gears S2 and T7 rotatable thereon, said compound gear S2 engaging with said loosely mounted gear 89 and said compound gear 77 meshing with a change gear 7G secured to said index shaft Si and rotatable therewith.

5. The combination of an index shaftXS, and index drive shat't (Si, a change gear 83 mounted on index drive shaft G, and rotatable therewith, a second change gear Si? loosely mounted thereon, a swinging ahoe do rota'talilv mounted on said index drive shaft (ietf, carrying a compound stud SS, compound xgears 84 and S5 rotatably mounted on said. stud 88 meshing with said gears 89 and S3 respectively, aV second swinging shoe 79 rotatably mounted on Said index shat't del carrying a second compound stud and compound gears .SQ and 7T rotatable thereon, said compound gear 89 ener' raging with said loosely mounted gear 89,

and said compound gear T7 meshing with a change gear U5. secured to said index shaft Si and rotatable therewith.

6. The combination of an index drive shaft, an index shaft, change gears connecting said shafts. a gear secured to said index shaft, a tumbler lever rotatably mounted on said index shaft carrying two tumbler gears one of `which engages with said gear on said index shaft. a, secondarfshatt, a gear secured to said secondaryshaft, and arranged to be engaged by each ot said tumbler gears,

a feed drive shaft, change gears connecting saidffeed drive and secondary shafts, .and means for securing said tumbler lever against said rotation when either of said tumbler gears are engaged.

7,In a helical gear cutting machine, the cen'ibination with a blank spindle, of an index shaft connected therewith, a cutter shaft, a feed shaft to feed saidv cutter shaft o substantially parallel with said blank spin-A dle, a main shaft, driving connections be-- ,tween said index and niaiiishafts, other driving connections between said cutter and main shafts, said driving connections arranged to produce a relative' rotational ratio between said cutter shaft and blank spindle, a driving means connecting said index and feed shafts, said driving connections and means arranged to produce a helical line passing around the axis of said said spindle, a main shaft, driving connections between said index and main shafts,

other driving connections between said cutter and main shafts, said driving connections arranged to produce a relative ro- 55 tational ratio -between said cutter shaft and spindle, a driving means connecting said index and feed shafts whereby said cutter shaft is fedl relatively to the rotations of said blank spindle, said relative 4relations combined to produce a helical line passing around the axis of said blank spindle, and

i means actuated by said main shaft to ret'urn said cutterand blank spindle to their original position without destroying th'e 4L, synchronism, substantially as described.

9. The combination of a main drive shaft,

a cutter carriage, a cutter spindle angu.

'larlyadjustablc thereon, gearing cbnnccting said`mainv drive shaft and 'cutter spindle,

an index feed shaft to. actiiajte said "cutter carriage, gearing connectingsaid index and feed s lgafts, an index driving shaft, gearinglgconnecting said main drive and 1ndex driving "shafts comprising means to rotate said index driving shaft slowly in one direction, when feedin said cutter, with ineansfor rapidly rotating said index driving shaft in the opposite direction, to return said cutter to its original position, and

changegears to connect said index drivin and index shafts substantially as describe j 10 the combination of a main drive shaft, :a cutter carriage,.a cutter spindle angularly adjustable thereon, gearing connecting said main drive shaft and cutter spindle, an indiiferent speeds, a clutch to alternately con" neet saidA driving members with said index driving shaft, to slowlv feed and rapidly return said cutter to its original position, and change gears to connectsaid index and index driving Yshafts substantially as def scribed.

11. Tliecombination of a main drive shaft, a cutter carriage, a cutter spindle angularly adjustable thereon, gearing connecting said main drive shaft and cutter spindle, an index shaft, a feed shaft to actuate said cutter carriage, gearing connecting said index and feed shafts, an index driving shaft, gearing connectingt said main drive and index driving. shafts comprising; two oppositely rotating driving members rotating at different speeds, a clutch to alternately connect said driving members with said index' driving shaft, to slowly feed and rapidly re-y turn said clutch to its original position,said clutch arranged to .engage'saidslow moving driving member in one position only, to preserve the relative rotational ratios-betweenv said cutter and spindle and feeding means,

and change gears connecting said index and indexing driving shafts, substantially as described` 12. In' a gear cutting machine in combination with a. main driving shaft., two oppositely disposed cuttercarriages, a cutter angularly adjustable, mounted upon .each j of said carriages, reversing ears upon said main drive shaft whereby t e direction of rotation of both cutters can be reversed, two feed shafts to actuate said carriages, an index shaft, a spindle carriage with a.

spindle rotatably mounted therein and actuated by said index shaftpatrain of gearing connecting said main drive shaft and, cutters, a second train of gearing connecting said main drive shaft and index shaft, a third train connecting said indexand feed' shafts, comprising reversing gears for each of said feed shafts w1 reby'the feed of each cutter can be individually reversed, said trains designed to produce a fixed rela-v tive rotational ratio between said cutter and spindle and producing affeeding motion relative to the rotations of said spindle,

to produce substantially a motion of twoA helical lines passing around the axis of said spindle substantially as described.

13. In a gear cutting machine the cornbination with a main drive 'shaft of two oppositely disposed cutter carriages, a cutter mounted upon each of' said .carriages and Asingularly adjustable thereon, ,reverslng gears upon said main drive shaft,

whereby theA direction ofrrotation of both cutters can be reversed, two feed shafts to act'uate said carriages, an inde/xV shaft, a spindle carriage, a spindle rotatably mounted therein and actuated by said indexvshaft, a train of gearing connecting said main drive .shaft and cutters, a second train of gearing connecting said main drive' and index shafts, a third train of'y gearing connecting said index and feed shafts, said trains designed to produce a fixed relative rotational ratio between said cutter kand spindle and producing a feeding motion relative to said spindle, to produce substantiallyA a motion of helical lines passing around the avis of said spindle, substantially as described;`

14. ln a gear cutting machine, the coinbination with a inain drive sha-ft of two oppositely' disposed vcutter carriages, a cutter mounted upon each of said carriages, and angularly adjustable thereon, two feed shafts to Yactua-te said carriages, an index shaft, a, spindle carriage, a spindle rotat- J ably mounted thereinl and actuated by said index shaft, a train of gearing connectin said main drive shaft and cutters', a secon train of gearing connecting said main drive and index shafts, a third train connecting said index and feed shafts, coniprisingfreversing gears whereby the feed of each cutter can be reversed, said trains designed to produce a` fixed relative rotational ratio between said cutter and spindle, and producing a feeding motion relative to the rotation of said spindle,` to produce substan tiallya motion of helical lines passing around the axis of said spindle,v substantially as described.

15. In a gear cutting machine,'the coinbination. with a main drive shaft of two oppositely disposed cutter carriages, a cutter mounted upon each of said carriages and angularly adjustable thereon, two feed shafts to. actuatefsaid4 carriages, an index Shaft, a spindle carriage,aspindle rotatably mounted therein and actuated by said index shaft, a train of gearing connecting said main drive shaft and cutters co1nprising a common4 reversing means operable from said main drive shaft whereby the direction of rotation of both cutters can be reversed, a second train of gearing connecting said inain drive and index shafts, a

third train of gearing connecting said index and feed shafts, said trains designed to produce a fixed relative rotational ratio between said cutter and spindle and'producing a feeding motion relative to said .spindle, to 'produce substantially a motion of helical lines passing around the axis of said' spindle, substantially as described.

16. In a gear cutting machine, the combination with a main drivershaft of two oppositely disposed cutter carriages, a cutter mounted upon each of said carriages and angularly adjustable thereon, a train of gearing connecting said main drive shaft and cutters, a common reversing means operable from said inain drive shaft, whereby t-he direction ofdrotation of both cut ters can be reversed, two feed shafts to actuate said carriages, an index shaft, a spin dle carriage, a spindle rotatably-mounted therein and actuated by said index shaft, a

`second trainof gearing connecting said Vitnesses:

EDWIN C. TiiUns'roN, BnNJAMiN NITTINGER. 

